Hydraulic ingredient and process of making same



UNITED STATES PA NT OFFIC EERDINAND ivroarrz MEYER, or SAARBRUCKEN,GERMANY, ASSIGNOR, BY MEsNE ASSIGNMENTS, TO THE cnEMIoa'L FOUNDATION,me, A CORPORATION OF DELA- WARE.

HYDRAULIC TNGREDIENT AND PROCESS OF MAKING SAME.

No'Drawing. Application filed January 3, 19 14,"Serial No. 810,198.

' a No. 332,440 17.

To all whom it may concern Be it known that I, FERDINAND Monrrz MEYER, asubject of the Emperor-of Germany, and a resident of Saarbrucken,Germany, have invented certain new and useful Improvements inHydraulicIngredient and Processes of Making Same, of which the following is a specification.

The object of the present invention is the production of a material,which is capable of giving hydraulic setting powers to hydraulic lime,or ordinary lime, or lime mortar. The present invention does not relateto the production of a material which is properly called ahydrauliccement, since the calcined, or calcined and crushed materialitself (without the addition of lime or hydraulic lime) when mixed withwater, does not harden, as does hydraulic cement.

My improved process is based upon the manufacture and-use ofpredetermined compounds from lime and claywhichwhile possessing noconsiderable setting power, when used alone, have the power ofmaterially in creasing the binding and setting power-of mixtures of lime(or its'equivalent) with sand, which mixtures, by themselves are onlyslightly hydraulic.

The first part of my improved process produces a product which by itselfhas no binding power at all or at most has only a very slight bindingpower, but which has the property of imparting a considerable degree ofhydraulicity to mortars containing lime, clay or silicious lime. Themortars made by adding the new ingredient to mortar, have a veryexcellent strength which considerably exceeds that of cements madeaccording to known processes' Thus, the

primary object of this invention is to manu facture not a cement, but ahydraulic in gredient which itself does not possess the properties of acement. 7

In my improved process there are particu larly two points which occasionthese important new properties of the product to be made :firstly, thepercentage of lime is considerably lower than that employed in theordinary processes of making hydraulic cement. Secondly, the temperatureis kept lower than in the ordinary processes in making cement, at anyrate, so low that sintering shall not take place.v

One form of the process for making such Specification of Letters Patent..Patented J 1 1116 22, 1920.

Renewed October 22, 1919. Serial a body capable of increasing thehydraulic properties of lime or hydraulic lime, which is essential inthe present process for increasing the hydraulicity and the strength oflime is as follows: \Vhen clay is mixed with chalk, dolomite, magnesite,soft'lime, such as is known in Germany as meadowlime (\Viesenkalk), ormarl in such a manner that a mixture is produced which titrates be tween25-50% calcium carbonate, and a corresponding quanity of a'flux, say 5%calcium chlorid is added, the mixture being heated. to 800 0., anunsintered mixture is obtained which, when ground and treated withwater,

hardens only very slightly. If thisground product is mixed' with burntlime. or hydraulic lime (as in the production of mortar), productsarethen obtained which become exceedingly hard both in theair and in water.

The lightly calcined product with three parts by weight of sand, takenaccording to the standards for Portland cement, is mixed, for example,with parts by weight of burnt lime or hydraulic lime; The :followingstrengths are thenfound (measured by the German standards for testingPortland cement and hardening after 28 days). In the table, A designatesthe new productalone, B burntlime, C hydraulic lime, D a mixture of 25parts of A and 75 parts of burnt lime (fat lime), E a mixture of 25parts of the new product and 7 5 parts of hydraulic lime.-

l p I Table.

' Air-hard- Combined Waterening. hardening. hardening.

, Com- Com- Com- Ton- 'lcn- 'le presprespros- Slon" sion. S1011 S1011510D slou s 40 11' 40, 4 1e 7 24 '0' 35 0 25 9 40' 11 4Q 5 16 16 109 16113 14 91 37 201 30 243 25 201 i This table shows the exceedingly greatand quite surprising hardening action of the new product. p r a v I Itis well known that Portland cement, granulated blast-furnace slag andalso trass exercise on lime a relatively small-hardening action; none ofthese bodies, however, acts even approximately in the same mannerlimestone,

as does the herein described new product which is quite different fromthose mentioned above both in its composition and in its mode ofproduction;

It is also well known that good hydraulic limes can be made by carefullyburning clayey limestones. These harden, however, by themselves, whereasin contradistinction thereto the new product develops its energy only incombination with large quantities of lime. It is also well known that amixture of clay, feldspar, lime and calcium chlorid may be calcined forthe purpose of liberating the alkali of the feldspar.

The sintering of clay and lime with the aid of chlorid of calcium is awell known chemical reaction frequently employed for quantitativelydetermining alkalis in feldspar and clays.

The new product can be made wherever there are suitable raw materials.By means of the present invention, a product having a strengthapproximately equal to that of Portland cement or of the best mortar canbe produced, and this without large expenditure of fuel or the necessityof extensive apparatus.

Additional investigations have shown that fluorspar and cryolite act ina manner similar to the calcium chlorid mentioned above.

If a mixture of aluminum hydroxid and calcium carbonate in theproportions theoretically necessary to form calcium aluminate is burntin the counter-current furnace at 800 C. (under the same conditions asstated in the above example of the manufacture of the hydraulicingredient) no chemical compound having the properties of Al,O .,CaO isobtained; the Ca() and Al. remain substantially uncombined. It followsthat aluminate fluxes do not play any material part in the hereindescribed process.

I claim 1. A process for making a hardening material for lime mortarconsisting in burning a mixture containing clay and about twentyfive tofiftv per cent. of calcium carbonate and a small proportion of a fluxingagent at a temperature below the clinkering point, but high enough todrive off most of the C0, of the carbonate, to produce a product whichreacts slowly with water.

2. In the process of making mortar having high setting power, the stepsof burn-- ing a mixture containing clay and about twenty-five to fiftyper cent. of calcium'carbonate and a small proportion of a flux at atemperature below the clinkering temperature of said mixture, but highenough to burn the CaCO, to CaO, to produce a prod not which reactsslowly with water, and

thereafter mixing the product thereby obtained with lime and sand in thepropor tion of about one part of said product to materially greateramounts of both lime and sand.

3. A process of making an agent capable of increasing the hydraulicproperties of mortar, which comprises burning a mixture containing clayand calcareous material, which mixture contains a percentage ofcalcareous material which is equivalent to not over 50%, calculated asCaCO together with a relatively small amount of a salt of which thesintering temperature is below that of the mixture, said burning beingconducted at a temperature below the temperature necessary for sinteringor clinkering the entire mass.

4. A process of making an agent capable of increasing the hydraulicproperties of mortar, which comprises burning a mixture containing clayand calcareous material, which mixture contains a percentage ofcalcareous material which is equivalent to not over 50% calculated asCaCO together with a relatively small amount of calcium-chlorid, saidburning being conducted at a temperature below the temperature necessaryfor sintering the entire mass.

5. As a new product, .a calcined but not clinkered mixture ofclay-containing materials, between about 15.7% and about 35.9% of Ca(),and a smaller amount of a salt capable of sintering at a temperaturebelow the sintering temperature of the entire mix ture, said productbeing, when alone, without any considerable hardening properties, butcapable of greatly increasing the hardening properties of hydraulic ornon-hydraulic limes, or mortars, including such limes, and said productbeing capable of reactingslowly with water.

6. As a new product, a calcined but not clinkered. mixture ofclay-containing mate rials, and between about 15.7% and about 35.9% ofOaO, and a smaller amount of calcium chlorid, said product being, whenalone, without any considerable hardening properties, but capableofgreatly increasing the hardening properties of hydraulic or nonhydrauliclimes, or mortars, including such limes, and said product being capableof reacting slowly with water.

In testimony whereof, I afiix my signature in the presence of twowitnesses.

FERDINAND Monrrz MEYER.

Witnesses MARIA MEUKE, Momrz WETZEL.

